If your car's electrical system seems to be going haywire, you may wonder whether the problem is being caused by a near-dead battery or a failing alternator. If so, look for the following telltale signs the issue is caused by your alternator.
1. Interior Electronics Have Stopped Working Properly
One of the first things you may notice when you have a failing alternator is when your interior electronics have stopped working properly while your car is running. While the battery usually feeds your radio and car seats while the engine is off, the alternator takes over once you start up the car.
You may find that your radio's speakers go in and out as you drive, especially when you use more power during acceleration. This happens because the alternator cannot handle the demand of both your engine and radio, so your motor takes priority.
As far as your car seats, you may find that they move slower when you try to adjust them. If they work right while the engine is off but slow down when it is running, this points to a problem with your alternator.
2. Headlights Start Acting Strangely
As with your interior accessories, your headlights are fed by the battery while the car is not running then switches to the alternator when you drive. If your alternator is going bad, your headlights will start acting strangely.
One moment, your headlights will shine as brightly as they are supposed to. However, when you step on the gas, they may dim or start to flicker because the alternator cannot provide the right amount of power.
Then, when you let off of the gas, you may see that the headlights grow brighter than they usually are right before they dim again. When this happens, a temporary power surge is sent to the headlights from the alternator. If the power surge becomes too much, you risk having the lights blow out while you are driving down the road.
As the alternator continues to fail, you may find that the lights come on when you switch on the ignition, but they refuse to stay on once you start your engine. If this is the case, your alternator is getting ready to die completely and needs to be inspected immediately.
If your car is exhibiting any of the above behaviors, your alternator is most likely going bad and will need to be replaced soon. Take your car to an auto repair service as soon as possible so they can test the alternator and discuss your options.